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The PtO2-catalyzed hydrogenation of curcumin produced slightly predominant meso-octahydrocurcumin than raceme octahydrocurcumin. Similar result was found in the product obtained from tetrahydrocurcumin and NaBH4, whereas using palladium carbon as a catalyst increased the meso-octahydrocurcumin ratio. Compared with chemical methods, baker's yeast produced 3S,5S-octahydrocurcumin and meso-octahydrocurcumin from tetrahydrocurcumin. The different activity between raceme and meso-octahydrocurcumin was not found in our experiments.

Summary Background. Photoageing of skin is thought to be caused by protein denaturation, which can be induced by ultraviolet radiation. Previous studies have also reported that inflammation is related to protein denaturation; however, the influence of inflammation on skin ageing has not been explored in detail. Aim. To investigate the possible connection between inflammation and protein denaturation, which might lead to skin ageing, we focused on halogenated tyrosine as a denatured substance produced during the inflammation process. Methods. We measured halogenated tyrosine in aged human skin. Inflammatory cells and halogenated tyrosine were detected by immunohistochemistry using antibodies to mast-cell tryptase, neutrophilic myeloperoxidase and halogenated tyrosine. Finally, using elastic van Gieson (EVG) staining, we investigated whether the sites of halogenated tyrosine coincided with the sites at which proteins were denatured. Results. Immunohistochemical analysis indicated that both inflammatory cells and halogenated tyrosines increased with ageing in both photoexposed and photoprotected skin. EVG staining confirmed that the localization of halogenated tyrosine was close to the sites at which protein was denatured. Conclusions. Our investigations indicate a possible connection between skin ageing and inflammation, suggesting that halogenated tyrosine could be a useful marker of ageing skin.

Antioxidants having a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity in rice mold starters, which are used for the preparation of various Japanese fermented foods, and their effectiveness against the expression of blood adhesion molecules were examined. An antioxidant was isolated from the rice mold starters used for shochu and identified as pyranonigrin-S (PG-S) by (1)H-NMR, (13)C-NMR, and FAB-MS analyses. It was a derivative of pyranonigrin-A (PG-A), which has been isolated as an antioxidant from the rice mold starters. Pyranonigrins PG-A and PG-S were found to exist in spores on rice mold starters which had been prepared by Aspergillus awamori, A. kawachii, and A. saitoi. PG-S exhibited a higher level of DPPH radical scavenging activity than PG-A. PG-A was found to have a significant suppressive effect on the expression of vascular cell adhesion molecule-1 (VCAM-1) in human umbilical vein endothelial cells (HUVECs) induced by tumor necrosis factor-alpha (TNF-alpha) (P0.05).

The antimicrobial activities of the three diterpene dialdehydes, miogadial, galanal A and galanal B, isolated from flower buds of the myoga (Zingiber mioga Roscoe) plant were investigated with some strains of bacteria, yeasts and molds. Among the three compounds, miogadial exhibited relatively greater antimicrobial activity than the others against Gram-positive bacteria and yeasts. Galanals A and B also behaved as antimicrobial agents against Gram-positive bacteria and yeasts. The content of miogadial in the flower buds was much higher than that in the leaves, whereas galanals A and B were contained at high levels in the leaves and rhizomes.

One- and two-dimensional (1)H nuclear magnetic resonance ((1)H NMR) spectra were measured in order to estimate the dissociation constants (K(diss)) and molecular geometries of cyclodextrin (CD) with three organic isothiocyanates (ITC), allyl-ITC, 3-butenyl-ITC, and 4-pentenyl-ITC, in an aqueous solution (pH 5.0, I(c)=0.75 M). In every ITC, the K(diss) values decreased in the order of alpha-CDbeta-CDgamma-CD, and the three rod-like linear molecules of ITCs were accommodated with the best fit into the smallest cavity of alpha-CD. By rotating-frame nuclear Overhauser enhancement spectroscopy, cross peaks were found between the H-3 of alpha-CD and the H-1 of AITC. From the result, the molecular geometry of alpha-CD-AITC complex presume that the isothiocyanate group of AITC is located some where around the widening rim and a hydrophobic allyl group is included within the hydrophobic cavity of alpha-CD.

The effects of isothiocyanates (ITCs) on tumor necrosis factor-alpha (TNF-alpha) production by the J774A.1 mouse macrophage cell line stimulated with lipopolysaccharide (LPS) were examined. Some individual ITCs examined showed a priming effect, which was expressed as pre-activation, but also inhibited the production of TNF-alpha with concomitant stimulation by LPS, as a triggering stimulant of TNF production. These results suggest that ITCs exert opposing activities that can enhance or inhibit the host defense system.

Inhibitors of excessive superoxide (O - 2) generation have been indicated to be more effective antioxidants than radical scavengers because O - 2 anion is one of the precursors of several types of reactive oxygen species (ROS). We demonstrated here that benzyl isothiocyanate (BITC) is a potent inhibitor of leukocytic NADPH oxidase generating a great amount of O - 2 in oxidative burst. The exposure of BITC to the differentiated HL-60 cells resulted in the inhibition of 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced O - 2 generation, while the methylthiocarbamate analog of BITC, hardly reactive with thiols including glutathione and protein sulfhydryl, did not show any effect. Pre-treatment of the cells with diethyl maleate significantly potentiated the BITC-induced inhibition, while pre-treatment with N-acetyl-cysteine counteracted it. These results led us to assume that a plausible intracellular target molecule(s) having a reactive sulfhydryl moiety might be regulated by the covalent attachment with BITC. In spite of no ability to affect the translocation of protein kinase C β to the membrane, BITC probably modifies the electron transport system of cytochrome b 558 , consistent with the observation that BITC inhibited the substrate utilization. Pre-treatments of mouse skin with BITC significantly attenuated the TPA-enhanced hydrogen peroxide level, suggesting that BITC indeed acts as an inhibitor of O - 2 generation in mouse skin. A histological study also demonstrated that BITC inhibited TPA-induced leukocyte infiltration in the dermis. Because we have found several O - 2 generation inhibitors to be effective chemopreventors against mouse skin carcinogenesis, the modifying effect of the topical application of BITC on TPA-induced mouse skin tumor promotion was investigated. We demonstrated for the first time that the pre-treatment with BITC 40 min prior to each TPA treatment significantly inhibited the number of papillomas per mouse. In conclusion, the results from this study provided biological evidence that BITC has a potential to prevent inflammation-related carcinogenesis including skin cancer.

Endogenous lipid peroxidation products react with DNA and form exocyclic DNA adducts. The purpose of this study was to investigate the in vivo formation of 7-(2-oxo-heptyl)-substituted 1,N(2)-etheno-2'-deoxyguanosine adduct (Oxo-heptyl-varepsilondG), one of the major products from the reaction of 13-hydroperoxyoctadecadienoic acid (13-HPODE) with dG. The monoclonal antibody specific to Oxo-heptyl-varepsilondG was prepared using a chemically synthesized conjugate of Oxo-heptyl-varepsilondG and carrier protein as immunogen. The characterization showed that the obtained antibody (mAb6A3) is specific to the Oxo-heptyl-varepsilondG moiety. Using the novel antibody, the presence of the Oxo-heptyl-varepsilondG adduct in vivo was immunohistochemically revealed in the liver of rats fed a choline-deficient, L-amino acid-defined diet, an endogenous carcinogenesis model, for 3 days. In addition, the Oxo-heptyl-varepsilondG formation was confirmed in DNAs treated with peroxidized linoleic acid, arachidonic acid and gamma-linolenic acid, respectively, suggesting that the hydroperoxides of omega-6 polyunsaturated fatty acids could be the potential sources of Oxo-heptyl-varepsilondG formation in vivo. Collectively, the results in this study suggest the first evidence that the formation of Oxo-heptyl-varepsilondG, the omega-6 lipid hydroperoxide-mediated DNA adduct, may be a potential biomarker for the early phase of carcinogenesis.

The development of food science in the near future probably depends on the advance in functional food science, the concept of which was proposed first in Japan nearly 15 years ago. The new science has been internationally distributed and accepted as conceptually being beyond nutrition. In Japan, however, it traced a unique path of progress in the form of a product-driven rather than concept-driven science. Actually, a number of substances and products with potential for disease risk reduction rather than simply for health maintenance have been investigated for their body-modulating functions. Some of them have been applied in practice to the industrialization of functional foods in terms of "foods for specified health uses" legally defined by new legislation. A variety of sophisticated methods have been introduced as well, including the so-called "XYZ" evaluation system, database construction for assessment of the function, and even the DNA microarray technique. The Ministry of Agriculture, Forestry, and Fisheries (MAFF) and the Ministry of Health and Welfare (MHW) also commenced their scientific as well as political activity, with its spread to industries which almost simultaneously began to vigorously investigate functional food products for enlargement of the food market. With all of this as a background, the Japan Liaison of the International Union of Food Science and Technology (IUFoST) hold a function food science symposium on behalf of related scientific bodies including the Japan Section of the International Life Science Institute (ILSI). This paper is an overview compiled from 12 presentations made in the symposium, with the aim of internationally publicizing the activity of functional food science in Japan.

This investigation evaluated the preventive effect of curcumin on radiation-induced tumor initiation in rat mammary glands. Fifty-four female rats were mated and then divided into two groups at day 11 of pregnancy. As the control group, 27 rats were fed a basal diet during the experimental period. As the experimental group, 27 rats were fed a diet containing 1% curcumin between day 11 of pregnancy and parturition (day 23 of pregnancy). All rats of both groups received whole body irradiation with 1.5 Gy gamma-rays from a (60)Co source at day 20 of pregnancy and were then implanted with a diethylstilbestrol pellet 1 month after weaning. A high incidence (70.3%) of mammary tumorigenesis was observed in the control group. The tumor incidence (18.5%) was significantly reduced in the rats fed curcumin during the initiation stage. The appearance of the first palpable tumor was delayed by 6 months in the curcumin-fed group and the average latent period until the appearance of mammary tumors was 2.5 months longer in the curcumin-fed group than in the control group. By histological examination, the proportion of adenocarcinoma (16.7%) in total tumors in the curcumin-fed rats was found to be decreased to half that (32.1%) in the control group. Compared with the control rats, the body weight of rats in the experimental group was decreased slightly by administration of the curcumin diet from day 11 of pregnancy, in spite of a similar intake of diet, but had recovered to the level of the control by the end of the experiment. At the time of irradiation, curcumin did not have any effect on organ weight or on the development and differentiation of mammary glands of pregnant rats. In addition, the serum concentrations of fatty acids, thiobarbituric acid-reactive substances and ovarian and pituitary hormones, except LH, remained at the control level. Also, no change in litter size and body weight of pups born from curcumin-fed rats indicated no toxicity of curcumin. These results suggest that curcumin does not have any side-effects and is an effective agent for chemoprevention acting at the radiation-induced initiation stage of mammary tumorigenesis.

Major photoproducts induced by carcinogenic ultraviolet (UV) radiation are the cylobutane pyrimidine dimers (CPDs) and pyrimidine-pyrimidone (6-4) photoproducts (6-4 PPs). 8-Hydroxy-2 -deoxyguanosine (8-OHdG) is also a DNA base-modified product generated by reactive oxygen species in conditions of ultraviolet stress, Although UVB-induced CPDs and 6-4 PPs have been investigated in animal and human skin, little is known about the role of 8-OHdG in UVB-induced human skin damage or carcinogenesis. Normal human skin from three volunteers was exposed to UV radiation, and the time course of induction and removal of 8-OHdG was examined by immunohistochemical analysis with catalysed signal amplification on formalin-fixed paraffin sections. Formation of CPDs and 6-4 PPs was also examined by immunostaining on the same skin specimens. Control epidermis with no exposure to UV radiation showed little nuclear staining of 8-OHdG, but an increased level of 8-OHdG was clearly observed in epidermis biopsied after irradiation. Induced 8-OHdG can rapidly be removed from nucleus during the first 24-48 h, as the staining intensity diminished gradually, almost reaching the control level by 72-96 h after irradiation. Staining for CPDs or 6-4 PPs revealed induction of these photoproducts in human skin, although 6-4 PP-positive cells disappeared more rapidly than those that stained for CPDs or 8-OHdG. Together with protective effect of antioxidants, our results indicate that not only CPDs and 6-4 PPs but also 8-OHdG may play a significant part in UV carcinogenesis.

It has been established that the covalent modification of proteins occurs in vivo as a consequence of reaction with reactive lipids such as 4-hydroxy-2-nonenal (HNE). The fact that HNE occurs in blood under physiological as well as pathophysiological conditions suggests that erythrocytes undergo modification by HNE. Here we describe the immunochemical characterization of HNE-treated erythrocytes by demonstrating the Michael-type HNE addition to both membrane and cytosolic proteins. Exposure of erythrocytes to HNE (0-0.5 mM) for 2 h resulted in HNE labeling of multiple membrane proteins. Pretreatment of erythrocytes with a sulfhydryl reagent, N-ethylmaleimide (NEM), resulted in a significant decrease of HNE attached to the proteins, suggesting that HNE primarily reacts with the sulfhydryl groups of erythrocyte membrane proteins, whereas enhanced HNE labeling of the membrane proteins was observed when the erythrocytes were pretreated with H2O2 (0.1-5 mM) for 15 min. On the other hand, highly selective modification of a 30 kDa protein was observed in the hemolysates of erythrocytes treated with HNE. The protein, which represents a major intracellular target of HNE in erythrocytes, was identified as carbonic anhydrase, based on the observations that (i) a reverse-phase HPLC analysis of the chloroform/ethanol extract of HNE-treated erythrocytes detected two major proteins, which cross-reacted with anti-carbonic anhydrase antibody as well as with the anti-HNE adducts antibody, (ii) the chloroform-ethanol extraction of authentic carbonic anhydrase gave a similar HPLC pattern, and (iii) the HNE treatment of erythrocytes resulted in the partial inhibition of the carbonic anhydrase activity.

In order to develop a new type of antioxidative compound which has both the phenolic and beta-diketone moiety in the same molecule, we converted three known curcuminoids, curcumin (diferuloylmethane, U1), (4-hydroxy-3-methoxycinnamoyl)methane (U2), and bis-(4-hydroxycinnamoyl)methane (U3), which are the natural antioxidants of Curcuma longa L. (tumeric), to tetrahydrocurcuminoids (THU1, THU2, and THU3, respectively) by hydrogenation, and evaluated their antioxidative activity by using linoleic acid as the substrate in an ethanol/water system. Further, we used the rabbit erythrocyte membrane ghost and rat liver microsome as in vitro systems and determined the antioxidative activity of these curcuminoids. When we evaluated their antioxidative activity by these assays, it was found that THU1 had the strongest antioxidative activity among all curcuminoids in each assay system. THU1 has been reported to be one of the main metabolites of U1 in vivo [Holder et al., Xenobiotica, 8, 761-768 (1978)]. These results suggest that THU1 must play an important role in the antioxidative mechanism of U1 in vivo by converting U1 into THU1.

A potent antioxidative 6-hydroxydaidzein (6-OHD) was newly isolated from soybean koji fermented with Aspergillus oryzae. 6-OHD, in addition to 8-hydroxydaidzein and 8-hydroxygenistein, were found to be present in various fermented soybean products, including their koji. Considering that these o-dihydroxyisoflavones had strong antioxidative activities, they may contribute to protecting from oxidative deterioration during the processing of fermented soybean products.

(1993). Screening for Antioxidative Activity of Edible Pulses. Bioscience, Biotechnology, and Biochemistry: Vol. 57, No. 9, pp. 1606-1608.

The desmutagenic activity of various food components on C-nitro mutagens formed by the nitrite/sorbic acid reaction was assayed and several vegetable juices were found to be effective for eliminating the mutagenicity of the nitrite/sorbic acid system. Especially, the desmutagenic activity of pumpkin juice was investigated, and ascorbic acid, cysteine and other reducing compounds were found to be responsible for desmutagenic actions on 1,4-dinitro-2-methyl pyrrole, the main mutagen formed by the reaction of sorbic acid with sodium nitrite, by reduction of the conjugated C-nitro group to a C-amino group.

As a search for natural antioxidants from plant materials, strong antioxidative activity was observed in leaf waxes extracted from Eucalyptus species. A novel type of antioxidant was isolated from the leaf wax of Eucalyptus globulus and identified as n-tritriacontan-16,18-dione. Antioxidative activities were determined by different methods; a thiocyanate method, a thiobarbituric acid method, a total carbonyl value method and a weighing test. The anti-oxidant showed remarkable antioxidative activity in a water/alcohol system and was more effective than α-tocopherol and BHA; however, it has no antioxidative activity in an oil system.

Mutagen formation by the reaction of sodium nitrite with some sorbic acid analogs was investigated by using the microbial mutagenicity tests (rec-assay and Ames test) together with chemical examination using TLC, and it became clear that the conjugated dienoic carbonyl structure is essential for mutagen formation by the reaction with nitrite By a large scale reaction of sodium nitrite with sorbic acid methyl ester, 5-nitro-2,4-hexadienoic acid methyl ester and ethylnitrohc acid were isolated and identified as the mam mutagens The results led to the assumption that a nitro group adjacent to the double bond is an important factor to develop mutagenicity

Four stereoisomers of sesaminol were artificially produced after the intermolecular transformation of sesamolin by the presence of acid clay during the decolorization process used to commercially produce sesame oil. After isolating and purifying, the stereochemical structures of four stereoisomers of sesaminol were deduced mainly by the ^-NMR spectroscopic technique, and X-ray crystallographic analysis of the 3,5-dinitrobenzoate of one of the sesaminol epimers confirmed the relative stereochemistry of all four sesaminol isomers.

Antioxidative constituents in roasted sesame seed oil were studied mainly by an antioxidative assay and HPLC analysis, in comparison with unroasted sesame seed oil. The main active constituent in fresh roasted seed oil was γ-tocopherol, but after heating at frying temperature for 1 ~ 2 hr, this was identified as sesamol, which was produced by hydrolysis of sesamolin that is present to a large degree in roasted sesame seed oil. This conversion of sesamolin to sesamol is catalyzed by acids.

Our previous study revealed the presence of some potent antioxidative components other than γ-tocopherol and sesamol in sesame seed and oil. In the present study, the effective components were extracted from mashed sesame seed with acetone, followed by removal of triglycerides by freezing. The acetone extract showed strong antioxidative activity with the thiocyanate method and gave 4 active antioxidative substances after a series of chromatographic separations. The molecular formulae were determined to be C20H20O6 (P1), C20H20O7 (P2), C20H18O7 (P3) and C10H10O4 (P4). Compounds P1 and P4 were respectively identified as a bisepoxylignan analogue and trans-ferulic acid. Though preliminary structural data for P2 and P3 indicate them to be a sesamolin analogue and a sesamin analogue, respectively, work is currently underway to confirm this. The antioxidative activities were in the order of P3 >P2>P1 >P4. The same components were also obtained from the 80% ethanol extractable polar fraction of the sesame oil ca...

From leaves of Chrysanthemum morifolium two stimulants for root initiation in mung bean cuttings have been isolated and identified as chrysartemins A and B (I and II). These substances showed synergistic activity on rooting with indoleacetic acid and were proved to be constituents of the “cofactor 4” designated by Hess.

(1985). Sesamolinol, a Novel Antioxidant Isolated from Sesame Seeds. Agricultural and Biological Chemistry: Vol. 49, No. 11, pp. 3351-3352.